Perl/Useful hacks

From S23Wiki

[edit] Quote for s23 wiki

#!/usr/bin/perl
#
# Will put pre-existing text in wiki markup for presentation
# example:
#     <center>
#     <whitespace>'''Lyrics
#     <whitespace>'''Lyrics
#     </ center>

$prefix =" '''";    # to prefix each sentence in file

$file = "$ARGV[0]";
open(TEMP, $file) || die "Needs file name\n";
@raw=(TEMP);
close(TEMP);


foreach $line (@raw)
{
    $wholeline = "$prefix" . "$line";
}

[edit] Rename the contents of directory

• How to rename everything that ends with ".old " to the same name with ".new". Here's how to do it in Perl nicely:

foreach my $file (glob "*.old") {
  my $newfile = $file;
  $newfile =~ s/\.old$/.new/;
  if (-e $newfile) {
    warn "can't rename $file to $newfile: $newfile exists\n";
  } elsif (rename $file, $newfile) {
    ## success, do nothing
  } else {
    warn "rename $file to $newfile failed: $!\n";
  }
}

Thought there is much faster way to do this in bash i bet (link from here if you know of one)